JP2006165106A - Electronic component mounting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To mounting electronic components only on a good printed circuit board by identifying defective printed circuit boards from a plurality of printed circuit boards provided on a multiple chamfering board. <P>SOLUTION: The identifying parts 13 to 15 corresponding to printed circuit boards 7 to 9 are formed on the multiple chamfering board 2 formed of three printed circuit boards 7 to 9 where the predetermined circuit patterns are formed and a waste board 10 formed in the periphery of these printed circuit boards 7 to 9 and the external inspection is conducted for the printed circuit boards 7 in order to check whether these are defective or not. Resist is then coated on the identifying part 14 corresponding to the printed circuit board 8 which has been identified as the defective board with this external inspection. Thereafter, reflectivity of the light of the position corresponding to the identifying parts 13 to 15 is detected with a light sensor before mounting of electronic component and the electronic components are mounted only on the printed circuit boards 7, 9 which have been determined as the good boards as a result of the detection. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an electronic component mounting method for mounting an electronic component on each printed wiring board constituting a multi-sided board.

  Using a multi-sided board consisting of multiple printed wiring boards on which the same circuit pattern is formed and a discard board that is provided around the printed wiring board and integrally connects the multiple printed wiring boards, In general, an electronic component mounting board on which electronic components are mounted is efficiently manufactured.

In the manufacturing process of the electronic component mounting board, an appearance inspection is performed on the circuit pattern and the like of the printed wiring board before mounting the electronic component. When a defect is detected in the circuit pattern by this visual inspection, in order to identify the printed wiring board on which the defective circuit pattern is formed as a defective product, a magic or ink is placed on a predetermined portion of the printed wiring board or the multi-sided board. Marking (see Patent Documents 1 and 2). Further, defective printed wiring boards are identified by sticking a sticker or marking by punching a board instead of marking by magic or ink.
JP-A-8-186400 Japanese Patent Laid-Open No. 11-40999

  However, as described in Patent Documents 1 and 2, the marking by magic or ink disappears when the marking portion is rubbed. There is also a problem that the marking disappears because the magic and ink are dissolved in the cleaning liquid in the cleaning process for the multi-sided substrate. Further, there is a concern that the cleaning liquid is contaminated by the dissolved ink. In addition, when sticking a sticker, fine dust such as paper fibers generated from the sticker is generated, which greatly affects product performance. Furthermore, when a solder paste is applied to a plurality of printed circuit boards simultaneously with a metal mask on the circuit pattern, the solder paste smears on the circuit pattern due to the level difference of the sticker. There is. Further, when a hole is made in a printed wiring board, scraps are generated, and the product performance is greatly affected by the mixing of dust. Further, there is a problem that other multi-sided substrates are damaged by burrs generated when holes are made.

  The present invention has been made in view of the above problems, and provides an electronic component mounting method that reliably identifies defective printed wiring boards from multi-sided boards and mounts electronic components only on non-defective printed wiring boards. For the purpose.

  In order to solve the above problems, an electronic component mounting method according to the present invention provides a multi-sided board including a plurality of printed wiring boards on which a predetermined circuit pattern is formed, and a discard board formed around the printed wiring boards. Identification parts corresponding to each of the printed wiring boards are formed, and each printed wiring board is inspected as to whether it is a defective product, and the printed wiring board determined as a defective product by this inspection. Or after applying a resist to the identification portion corresponding to one of the printed wiring boards determined to be non-defective, the light reflectance or color density of the position corresponding to the identification portion is detected, An electronic component is mounted only on the printed wiring board determined to be non-defective based on the detection result.

  Moreover, it is preferable that the said identification part is provided in at least any one among the said discard board or the said printed wiring board. Moreover, it is preferable that the said identification part is formed with copper foil. Further, at least a part of the circuit pattern may be the identification unit.

  According to the electronic component mounting method of the present invention, a plurality of printed circuit boards on which a predetermined circuit pattern is formed, and a multi-sided circuit board made up of discarded boards formed around these printed circuit boards, each printed circuit board. Corresponding identification part is formed, and each printed wiring board is inspected whether it is defective or not, printed wiring board determined as defective by this inspection, or printed wiring determined as good After applying a resist to the identification part corresponding to one of the substrates, the light reflectance or color density at the position corresponding to the identification part is detected, and the print determined to be non-defective based on the detection result Since the electronic components are mounted only on the wiring board, the defective printed circuit board is surely selected from the multi-sided printed circuit board, and only the good printed wiring board is electronic. Since implementing goods, can save time for mounting electronic components on a printed wiring board defective, work efficiency is improved.

  Moreover, when the identification part is formed on the discard board, the printed wiring board can be reduced in size, and the space of the printed wiring board can be used effectively. Further, when the identification portion is formed on the printed wiring board, the multi-sided board can be reduced in size. In addition, when the identification part is formed on the discarded board and the printed wiring board, the defective printed wiring board is identified before mounting the electronic component and when the printed wiring board is divided from the multi-sided board. Therefore, the defective printed wiring board can be surely removed. Further, when at least a part of the circuit pattern is used as the identification unit, it is not necessary to newly form the identification unit, and the effective use and work of the multi-sided substrate space can be simplified.

  As shown in FIG. 1, the multi-sided board 2 includes three printed wiring boards 7, 8, 9 having the same circuit pattern 6 formed on each board piece 4, and the periphery of these printed wiring boards 7-9. The enclosure includes a discard plate 10 that integrally connects the three printed wiring boards 7 to 9, and a removal unit 12 that easily divides the printed wiring boards 7 to 9 from the discard board 10.

  Further, the discard plate 10 is provided with identification portions 13 to 15 corresponding to the printed wiring boards 7 to 9. The identification portions 13 to 15 are formed when the circuit pattern 6 is formed, and are formed of the same copper foil as the circuit pattern 6. In addition, although the shape of the identification parts 13-15 is circular, it is not restricted to this. Moreover, although the identification parts 13-15 were formed with copper foil, it is good also as the identification parts 13-15 by exposing the glass epoxy resin which has formed the multi-cavity board | substrate 2. FIG.

  The flowchart of FIG. 2 shows a procedure for forming an electronic component mounting board in which electronic components are mounted on the printed wiring boards 7 to 9. A predetermined circuit pattern 6 is formed on each substrate piece 4 by known etching or the like. After the circuit pattern 6 is formed, defective products of the printed wiring boards 7 to 9 are determined by appearance inspection. This visual inspection is performed by visual observation by an operator, and an electronic camera that reads images of the printed wiring boards 7 to 9 and the circuit pattern 6 and an image determination device that analyzes an image obtained from the electronic camera are used. Done. When using the image discriminating apparatus, the image of the good printed wiring board and the circuit pattern 6 stored in advance is compared with the image obtained from the electronic camera, and if both do not match, it is determined as a defective product.

  As a result of the appearance inspection, for example, when the circuit pattern 6 of the printed wiring board 8 is determined to be defective, a black resist is applied to the identification unit 14 corresponding to the defective printed wiring board 8. . As a result, a resist layer 18 is formed on the identification portion 14. In addition, since the resist is not applied to the identification parts 13 and 15 of the printed wiring boards 7 and 9 that are determined to be non-defective products by the appearance inspection, the copper foil remains exposed. Therefore, the reflectance of light differs between the position corresponding to the identification part 14 of the defective printed wiring board 8 and the position corresponding to the identification parts 13 and 15 of the non-defective printed wiring boards 7 and 9. Note that there are two types of resists, a positive type and a negative type. In this embodiment, a positive type is used. The positive type has the property that it is difficult to dissolve in chemicals when irradiated with light. The negative type is the opposite of the positive type and is easily dissolved in chemicals when irradiated with light.

  After the appearance inspection, a metal mask is placed on the circuit patterns 6 of the printed wiring boards 7 to 9, and cream solder printing is performed collectively on the parts necessary for component mounting of the circuit patterns. Thereafter, the multi-sided board 2 is moved to a component mounting process through board cleaning and the like.

  In the component mounting process, the defective printed wiring board 8 is identified before the electronic component is mounted. For this identification, an optical sensor having a light emitting / receiving optical element is used. The optical sensor is a reflective optical sensor that detects a ratio (that is, reflectance) of reflected light intensity to incident light intensity. The light projecting unit of this optical sensor projects light to the identifying units 13-15. And in a light-receiving part, the reflected light reflected in the identification parts 13-15 is received. For example, when the copper foil is exposed as in the identification units 13 and 15 shown in FIG. 1, the amount of light received by the light receiving unit is equal to or higher than a certain level (high reflectance). Therefore, the printed wiring boards 7 and 9 corresponding to the identification units 13 and 15 are determined to be non-defective products. In addition, when the resist layer 18 is provided as in the identification unit 14, the amount of light received by the light receiving unit is below a certain level (light reflectance is low). Therefore, it is determined that the printed wiring board 8 corresponding to the identification unit 14 is a defective product.

  Note that the multi-sided board 2 is cleaned before the defective printed wiring board 8 is identified, but the resist layer 18 applied to the identification unit 14 is transferred until the multi-sided board 2 is transported and the board is cleaned. In the meantime, it is dried and irradiated with external light or illumination light. Therefore, the resist layer 18 is not dissolved by the substrate cleaning.

  Further, although the defective printed wiring board 8 and the non-defective printed wiring boards 7 and 9 are identified by the light reflectance at the positions corresponding to the identifying units 13 to 15, the present invention is not limited to this. Alternatively, it may be performed by using the color of the color corresponding to the identification units 13 to 15 using a CCD camera. In this case, the identification units 13 to 15 are photographed by a CCD camera, image processing is performed on the photographed images, and the shades of the identification units 13 to 15 are determined. If the identification portions 13 to 15 are darker than a certain level, it is determined that the printed wiring board is a defective product (resist layer 18 is formed). If it is lighter than a certain level, it may be determined as a non-defective printed wiring board (exposed copper foil). Moreover, the detection of the identification parts 13-15 may be performed at three places simultaneously, and may be performed one place at a time.

  When the identification of the printed wiring boards 7 to 9 is completed, electronic components are mounted on the circuit pattern 6 of the printed wiring boards 7 and 9 corresponding to the identification portions 13 and 15 where the resist layer 18 is not formed based on the identification result. The In addition, electronic components are not mounted on the printed wiring board 8 determined to be defective.

  When the mounting of the electronic components on the non-defective printed wiring boards 7 and 9 is finished, the cream solder printed on the necessary portion of the circuit pattern 6 is dissolved and the electronic components are soldered as described above. Thereby, a plurality of electronic component mounting boards are efficiently formed on the multi-sided board 2.

  Then, the electronic component mounting boards are separated from the connecting portions 10a provided on the discard plate 10, respectively. At this time, since no electronic components are mounted on the printed wiring board 8 determined to be defective, the cost can be reduced and the workability can be improved. Furthermore, since the identification parts 13-15 are not provided in the printed wiring boards 7-9, the printed wiring boards 7-9 can be downsized.

  In the above embodiment, the identification units 13 to 15 corresponding to the plurality of printed wiring boards 7 to 9 provided on the multi-sided board 2 are provided on the discard board 10 surrounding the printed wiring boards 7 to 9, respectively. As shown in FIG. 3, the connecting portions 10 a to 10 c of the discard plate 10 may be used as identification portions. Also in this case, when the printed wiring board 8 is determined to be defective by appearance inspection, a resist is applied to the connecting portion 10b corresponding to the printed wiring board 8, and a resist layer 18 is formed. Then, before the electronic component is mounted, the light reflectance of the connecting portions 10a to 10c is detected by the optical sensor, and the defective printed wiring board 8 is identified. As described above, when the connecting portions 10a to 10c are the identification portions, the width of the discard plate 10 around the printed wiring boards 7 to 9 can be made as thin as possible, so that the area of the printed wiring boards 7 to 9 is reduced. Can be bigger. Therefore, the space for forming the circuit pattern 6 is increased, so that a more complicated circuit pattern can be formed.

  In addition, when using the connection parts 10a-10c as an identification part, although it is preferable that the glass epoxy resin which forms a multi-sided board | substrate is exposed, the connection parts 10a-10c are not restricted to this. Further, in FIG. 3, the resist is applied to the entire connecting portion 10b, but the resist may be applied to a part of the connecting portion 10b.

  Moreover, in the said embodiment, the identification part corresponding to each of the printed wiring boards 7-9 is provided in the discard board 10 (including connection part 10a-10c), and the position of a position corresponding to an identification part is mounted before mounting an electronic component. The defective printed wiring board 8 is identified by detecting the light reflectance. However, the identification parts 25 to 27 corresponding to the printed wiring boards 7 to 9 may be provided in the printed wiring boards 7 to 9. In this case, as shown in FIG. 4, for example, identification units 25 to 27 are provided at one end of each printed wiring board 7 to 9. For example, a resist layer 18 is formed on the identification unit 26 corresponding to the printed wiring board 8 determined to be defective by the appearance inspection, and the identification units 25 and 27 of the printed wiring boards 7 and 9 determined to be non-defective are Copper foil is exposed. Thereby, the reflectance of the light of the position corresponding to the identification parts 25-27 is detected before an electronic component is mounted, and the printed wiring board 8 of a defective product is identified. Accordingly, electronic components are mounted only on the non-defective printed wiring boards 7 and 9. Since the identification units 25 to 27 are provided in the printed wiring boards 7 to 9, after the printed wiring boards 7 to 9 are divided from the multi-sided board 2 after mounting the electronic components, the printed wiring boards 7 to 9 are arranged. It is possible to easily confirm whether the non-defective product and the defective product are correctly identified.

  Moreover, in FIG. 5, although the identification parts 25-27 were provided in the one end part of each printed wiring board 7-9, the position which provides the identification parts 25-27 is set suitably. Furthermore, as shown in FIG. 5, at least a part of the circuit pattern 6 may be used as the identification units 6a to 6c. In this case, when a defective printed wiring board 8 is found by visual inspection, a resist is applied to the identification unit 6b. The printed wiring boards 7 to 9 before electronic components are mounted are identified by detecting the reflectance of light at positions corresponding to the identifying units 6a to 6c with an optical sensor. Thus, since the identification parts 6a-6c are a part of circuit patterns formed with copper foil, it is not necessary to form another identification part with copper foil, and work becomes easy. Further, the printed wiring boards 7 to 9 can be downsized. Although a part of the circuit pattern 6 is the identification units 6a to 6c, the entire circuit pattern 6 may be the identification unit.

  Moreover, in the said embodiment, when the identification parts 13-15 were provided in the discard board 10 as shown in FIG. 1, and the identification parts 25-26 were provided in the printed wiring boards 7-9 as shown in FIG. However, these may be used together as shown in FIG. In this case, it is preferable to make the area of the 1st identification parts 30-33 provided in the discard board 10 larger than the area of the 2nd identification parts 35-37 provided in the printed wiring boards 7-9.

  When the printed wiring board 8 is determined to be defective by the appearance inspection, a resist is applied to the first identification unit 32 and the second identification unit 36 corresponding to the printed wiring board 8 to form the resist layer 18. When the printed wiring boards 7 to 9 are identified before the electronic components are mounted, the light reflectance at the position corresponding to the first identifying units 30 to 33 having a large area is detected using an optical sensor. The By this detection, the printed circuit boards 7 and 9 are identified as good products and the printed circuit board 8 is identified as defective products. Based on this identification result, electronic components are mounted only on the non-defective printed wiring boards 7 and 9. Then, after each printed wiring board 7-9 is divided | segmented from the multi-chamfer board | substrate 2, the non-defective goods are confirmed reliably by visually confirming the color shading (presence / absence of the resist layer 18) of the identification portion 35-37 having a small area. It can be confirmed that electronic components are mounted only on the printed wiring boards 7 and 9. Therefore, it is possible to prevent an electronic component mounting board in which an electronic component is mounted on a defective printed wiring board 8 from entering the market by mistake. In addition, although the example which combined embodiment shown in FIG. 1 and embodiment shown in FIG. 4 was demonstrated, you may use embodiment of FIG. 1 and embodiment of FIG. 5 together.

  In addition, although the three printed wiring boards 7-9 were provided in the multi-sided board | substrate 2, it is not restricted to this, It is preferable to set suitably according to the magnitude | size of the circuit pattern 6, the multi-sided board | substrate 2, etc.

  In each of the above embodiments, the resist is applied to the identification unit 14 corresponding to the printed wiring board 8 determined to be defective by the appearance inspection, but the identification unit corresponding to the printed wiring boards 7 and 9 determined to be non-defective products. 13 and 15 may be coated with a resist, and the printed wiring board corresponding to the identification portion coated with the resist layer 18 may be identified as a good product. In addition, although the resist layer 18 is formed on the upper portion of the identification portion using a black resist, the color of the resist is not limited to black, and the light reflectance of the resist layer 18 and the identification portion where the resist is not applied. It is sufficient if the difference in light reflectance is greatly different.

It is a top view explaining the multi-sided board | substrate used for this invention. It is a flowchart which shows the procedure which performs electronic component mounting. It is a top view of a multi-sided board | substrate when an identification part is provided in a connection part. It is a top view of a multi-sided board | substrate at the time of providing an identification part in a printed wiring board. It is a top view of a multi-sided board | substrate when an identification part is provided in a part of circuit pattern. It is a top view of a multi-sided board | substrate when an identification part is provided in both a discard board and a printed wiring board.

Explanation of symbols

2 Multi-sided board 6 Circuit pattern 7, 8, 9 Printed wiring board 13, 14, 15 Identification part 18 Resist layer

Claims (5)

A plurality of printed wiring boards on which a predetermined circuit pattern is formed, and an identification portion corresponding to each of the printed wiring boards is formed on a multi-sided board made of a discarded board formed around these printed wiring boards, Inspecting whether each of the printed wiring boards is defective or not, and corresponding to either the printed wiring board determined to be defective by this inspection or the printed wiring board determined to be non-defective After the resist is applied to the identification unit, the light reflectance or color density at the position corresponding to the identification unit is detected, and the printed wiring board determined to be a non-defective product based on the detection result Electronic component mounting method characterized by mounting only electronic components.   The electronic component mounting method according to claim 1, wherein the identification unit is provided on the discard plate.   3. The electronic component mounting method according to claim 1, wherein the identification unit is provided on the printed wiring board.   4. The electronic component mounting method according to claim 1, wherein the identification part is formed of a copper foil. 4. The electronic component mounting method according to claim 1, wherein at least a part of the circuit pattern is the identification unit.

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